This document provides an overview of serverless functions using Python and AWS Lambda. It introduces AWS Lambda as a compute service that lets you run code without provisioning or managing servers, and pays only for the compute time used. It also discusses API Gateway for creating and maintaining APIs, and how to structure Python functions for Lambda. Example Python code is provided for Lambda function syntax, logging, and exception handling.

1. Serverless Function
With Python and
AWS Lambda

2. Hello!
Nice to meet you
My Name is Fitrah Elly Firdaus. I am Software
Engineer at Traveloka.
Contact me at:
▪ fitrah.firdaus@gmail.com
▪ @FEF123

3. Table of contents 1. AWS Lambda
2. API Gateway
3. Python With Lambda
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4. 1.
AWS
Lambda
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5. What is
AWS
Lambda
• Run code without thinking about servers. Pay only for the
compute time you consume.
• First 1M requests per month are free.
• 400.000 GB-Seconds of compute time per month, free.
• $0.20 per 1M requests thereafter, $0.0000002 per request.
• $0.00001667 for every GB-Second used thereafter
• Supported Language: Python, Go, Java, NodeJS, C#
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6. How It
Works
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7. Use Cases • Data Processing
• Real Time File Processing
• Real Time Stream Processing
• Extract, Transform and Load
• Backend
• IOT Backends
• Mobile Backends
• Web Applications
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8. Lambda
Designer
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9. 2. AWS API
Gateway
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10. What is API
Gateway
• Create, Maintain, and secure API at any scale
• First 1M API Calls per month are free
• $4.25 per million API calls received, plus the cost of data
transfer out, in gigabytes.
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11. What can be
integrate?
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12. 3. Python
With
Lambda
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13. General
Syntax
Structure
def handler_name(event, context):
...
return some_value
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14. What is
event?
• Usually python dict type
• list
• str
• int
• float
• NoneType
• Proxy Integration if using API Gateway
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15. What is
context
• This information usually contain
• How much time is remaining before AWS Lambda
terminates your Lambda function
• Cloudwatch log group
• AWS Request ID
• Mobile Application function, if called from mobile apps
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16. What is
context
Object
Methods
• get_remaining_time_in_millis()
• Returns the remaining execution time, in milliseconds,
until AWS Lambda terminates the function.
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17. What is
context
Object
attributes
• function_name
• function_version
• invoked_function_arn
• memory_limit_in_mb
• aws_request_id
• log_group_name
• log_stream_name
• identity
• client_context
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18. Format of a
Lambda
Function for
Proxy
Integration
{
"isBase64Encoded": true|false,
"statusCode": httpStatusCode,
"headers": { "headerName": "headerValue", ... },
"body": "...”
}
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19. How to log
the handler
import logging
logger = logging.getLogger()
logger.setLevel(logging.INFO)
def my_logging_handler(event, context):
logger.info('got event{}'.format(event))
logger.error('something went wrong’)
return 'Hello from Lambda!'
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20. CloudWatch
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21. How to
create
exception
def always_failed_handler(event, context):
raise Exception('I failed!')
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22. LITTLE DEMO
https://github.com/fitrah-firdaus/Simple-Crud-
Lambda-Python
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23. Thank you very much
for your time
23
If you have any questions about this document
please don’t hesitate to contact me at:
▪ fitrah.firdaus@gmail.com
▪ @FEF123
▪ @pythonID